Crate Vintage Club 30 Oddity

[Flynscot]

Ok. I've been going over the VC3112 for a while now, referencing the schematic while making notes for mods and also chasing this infernal fizz problem. I'm wondering if someone can enlighten me as to a portion of the circuit. Schematic for reference.

It appears that part of the output from V2 and V3 is pulled off (labeled HV), sent through a capacitor/resistor/capacitor (filter?), then is dumped into some of the v4 phase inverter output via a voltage divider, and ultimately ends up feeding (the grid of?) the power amp tubes.

So I guess my question is: What is the purpose of this voltage? It isn't signal input, as that takes a different path and gets sent to the PI and then a different input of the power tubes.

Is it bias-related? It looks from the schematic like even the clean channel feeds some output from V1 into at least part of V2 to produce this HV as well. What gives?

Also, the c14-r22-c15 combo in the HV. This appears to be a filtering scheme. Band pass maybe? I'm unsure.

I humbly await enlightenment.

[Flynscot]

Wait. I figured it out- voltage from power supply to anodes, right?

Duh. Was thinking backwards and not considering the whole schematic...

[dano-rator]

Yes! Tell him what he's won, Tom...

[Flynscot]

A football field full of marshmallows, maybe?

[Structo]

And crystal lettuce.

[sheeba]

Has anyone else come across this problem? Sounds Like static or vibration on lower notes. I hear it as the note decays mainly on the clean channel. Any input would be appreciated. All the solder joints are good. The 10000uf cap was replaced. The rest test well. Jacks were repaired. Tubes are new. Speaker is fine with other amps. The problem follows the amp.